Research interests are centered on the understanding and analysis of energy systems through experimental and simulation work, with the aim of transferring insights from basic research into practical applications. This includes the experimental study and analysis of energy conversion with the aim of modeling energy flows and pollutant emission formation, which has applications in the transportation and power generation sectors. These models can be used to develop optimal strategies for pollutant reduction, fuel consumption minimization, on-line emission control and remote monitoring of emissions. In addition, the use of alternative fuels in conventional combustion systems, as well as interdisciplinary collaborative work to determine environmental and health effects of emissions from conventional and novel combustion technologies and alternative fuels are of particular interest.
Recent research has focused on the development and application of phenomenological models of (spray) combustion and emission formation. The aim of the models is to be computationally efficient and thus be suitable for optimization and on-line control purposes, while being physically and chemically consistent and thus accurate in a wide range of operation and under changing boundary conditions, as well as for different power unit sizes which exist for different applications.
The understanding of physical and chemical processes is built through an interdisciplinary approach combining experimental research coupled to high fidelity simulations:
- Optical methods for non-reactive and reactive spray measurements are used in fundamental experimental test rigs, in order to provide an understanding of the individual parameters which influence combustion and especially emission formation under well-controlled conditions. This research is conducted within the Aerothermochemistry and Combustion Systems (LAV) group in ETH as well as in collaboration with the Combustion Research Laboratory (CRL) in the Paul Scherrer Institut (PSI) and the Spray Combustion Chamber group in Winterthur Gas & Diesel Ltd.
- Experimental investigations on near-production and experimental combustion engines, which are used for the development, testing and validation of the phenomenological models. The engines measurements are performed in test facilities located in ETH within the LAV group and in collaboration with the IDSC group, as well as in PSI, on the Large Engine Research Facility (LERF), there.
- Investigation of highly-efficient, “near-zero” pollutant formation gas engines or combined heat and power generation. Beyond natural gas, several renewable fuels (biogas, ethanol, H2-admixture in CH4, synthesis gas are investigated with regard to their potential for low CO2 cogeneration.
- 0-D/1-D process thermodynamic calculations, which allow a better understanding of the engine systems as a whole providing supplementary information to the engine experiments and assist in the identification of possible areas for improved energy utilization in the future.
- 3-D computational reactive fluid dynamics simulations of the engines and combustion processes, in collaboration with the 3D CRFD group. The simulations employ models for the characterization of the physical-chemical interactions between turbulence and chemistry in single- and multi –phase reactive flows validated through measurements, are used to enhance the understanding obtained through the experiments, provide local information which is otherwise unavailable, and create a connection between fundamental experiments and practical applications.
On the aspect of the model development and applications, current research focuses on:
- The identification of important parameters which will be included in the computationally efficient combustion and emission models.
- The discovery of parameters to be used as inputs or as feedback to the models, which can be reliably measured using simple, robust and inexpensive sensors.
- Development and application of virtual emission sensors, to be used for engine feedback control and emission monitoring.